1. Technical Field
The present invention relates to a control method of an electro-optical device, such as an electrophoretic display device, a controller of an electro-optical device, an electro-optical device, and an electronic apparatus.
2. Related Art
Examples of an electro-optical device include an electrophoretic display device which displays an image on its display unit by applying a voltage between a pixel electrode and a counter electrode, which face each other with an electrophoretic element including electrophoretic particles interposed therebetween, in order to move electrophoretic particles, such as black particles and white particles, (for example, refer to Japanese Patent Publication No. 3750565 and JP-A-2010-113281). The electrophoretic element is formed by a plurality of microcapsules including a plurality of electrophoretic particles, for example, and is fixed between a pixel electrode and a counter electrode by an adhesive, such as a resin. In addition, the counter electrode is also called a common electrode.
When rewriting an image displayed on the display unit in such an electrophoretic display device, a driving method for rewriting an image partially by applying a voltage between the pixel electrode of only a pixel, which corresponds to a changed portion, and the counter electrode (hereinafter, appropriately referred to as “partial rewriting driving”) may be adopted if an image changes partially. In the electrophoretic display device in which such partial rewriting driving is adopted, for example, there is a possibility that the boundary of a black image portion displayed in black and a white image portion displayed in white in an image displayed on the display unit will be displayed in a blurred state. In other words, it is known that a contour portion of the black image portion may be displayed in a state spreading to the white image portion side (or in a bulging state) (for example, refer to JP-A-2010-113281).
When such a blurring of the boundary occurs, the blur of the boundary may remain as an afterimage if the entire image displayed on the display unit is rewritten to a white image by applying a voltage to only a pixel corresponding to the black image portion. In other words, an afterimage along the contour portion of the displayed black image portion may be generated. Hereinafter, such a phenomenon in which an afterimage along the contour portion is generated or such an afterimage itself along the contour portion is appropriately referred to as a “contour afterimage”. For example, JP-A-2010-113281 discloses a technique of eliminating a contour afterimage by applying a voltage so that a portion remaining as a contour afterimage (for example, a pixel which is disposed adjacent to a pixel corresponding to a contour portion of a black image portion and which is displayed in white) is also rewritten when rewriting an image displayed on a display unit by the partial rewriting driving.
In the technique disclosed in JP-A-2010-113281, however, processing for eliminating the contour afterimage is performed every image rewriting. For this reason, a period taken for the image rewriting becomes long. As a result, for example, display switching between a plurality of pages cannot be smoothly performed. This may degrade the usability significantly. That is, the technique disclosed in JP-A-2010-113281 has a technical problem in that new inconvenience is caused even if the contour afterimage generated at the time of image rewriting can be eliminated.